BACKGROUNDThis study sought to compare the effectiveness of aggressive versus nonaggressive treatment in reducing cancer-specific mortality for older men with early-stage prostate cancer across differing comorbid disease burdens at diagnosis.

METHODSIn total, the authors sampled 140,553 men aged ≥66 years with early-stage prostate cancer who were diagnosed between 1991 and 2007 from the Surveillance, Epidemiology, and End Results-Medicare database. Propensity-adjusted competing-risks regression analysis was used to compare the risk of cancer-specific mortality between men who received aggressive versus nonaggressive treatment among comorbidity subgroups.

RESULTSIn propensity-adjusted competing-risks regression analysis, aggressive treatment was associated with a significantly lower risk of cancer-specific mortality among men who had Charlson scores of 0, 1, and 2 but not among men who had Charlson scores ≥3 (subhazard ratio, 0.85; 95% confidence interval, 0.62-1.18). The absolute reduction in 15-year cancer-specific mortality between men who received aggressive versus nonaggressive treatment was 6.1%, 4.3%, 3.9%, and 0.9% for men with Charlson scores of 0, 1, 2, and ≥3, respectively. Among men who had well-differentiated and moderately-differentiated tumors, aggressive treatment again was associated with a lower risk of cancer-specific mortality for those who had Charlson scores of 0, 1, and 2 but not for those who had Charlson scores ≥3 (subhazard ratio, 1.14; 95% confidence interval, 0.70-1.89). The absolute reduction in 15-year cancer-specific mortality between men who received aggressive versus nonaggressive treatment was 3.8%, 3%, 1.9%, and -0.5% for men with Charlson scores of 0, 1, 2, and ≥3, respectively.